For the most part the digitized maps are derived from a library of maps of the Rhine region, a collection the Landesbibliothekszentrum Rheinland-Pfalz acquired from Prof. Fritz Hellwig. These maps cover the 16th up to the early 20th century presenting the Rhine valley in whole or in part from general surveys down to detailed plans. Examples of almost every important European manufacturer are presented within this collection, in which the monumental maps-most of them in several sheets-showing the river Rhine large scale from source to mouth are of outstanding significance.